Author(s): Guan, Z (Guan, Zhao); Zhao, YF (Zhao, Yifeng); Wang, XT (Wang, Xiaoting); Zhong, N (Zhong, Ni); Deng, X (Deng, Xing); Zheng, YZ (Zheng, Yunzhe); Wang, JJ (Wang, Jinjin); Xu, DD (Xu, Dongdong); Ma, RR (Ma, Ruru); Yue, FY (Yue, Fangyu); Cheng, Y (Cheng, Yan); Huang, R (Huang, Rong); Xiang, PH (Xiang, Pinghua); Wei, ZM (Wei, Zhongming); Chu, JH (Chu, Junhao); Duan, CG (Duan, Chungang)

Source: ACS NANO DOI: 10.1021/acsnano.1c09183 Early Access Date: JAN 2022

Abstract: Searching van der Waals ferroic materials that can work under ambient conditions is of critical importance for developing ferroic devices at the two-dimensional limit. Here we report the experimental discovery of electric-field-induced reversible antiferroelectric (AFE) to ferroelectric (FE) transition at room temperature in van der Waals layered alpha-GeSe, employing Raman spectroscopy, transmission electron microscopy, second-harmonic generation, and piezoelectric force microscopy consolidated by first-principles calculations. An orientationdependent AFE-FE transition provides strong evidence that the in-plane (IP) polarization vector aligns along the armchair rather than zigzag direction in alpha-GeSe. In addition, temperature-dependent Raman spectra showed that the IP polarization could sustain up to higher than 700 K. Our findings suggest that alpha-GeSe, which is also a potential ferrovalley material, could be a robust building block for creating artificial 2D multiferroics at room temperature.

Accession Number: WOS:000740503600001

PubMed ID: 34978807

ISSN: 1936-0851

eISSN: 1936-086X

Full Text: https://pubs.acs.org/doi/10.1021/acsnano.1c09183